Orcas Ram Sunfish Until They Explode in Gulf of California

Researchers documented orcas in the Gulf of California using a previously unrecorded feeding strategy in 2024 and 2025: ramming sunfish with such force that the fish fragment into thousands of pieces. The behavior was captured on video by marine scientists and tour operators near San José del Cabo in Mexico's Baja California Sur. In each recorded instance, one orca held a sunfish carcass (identified as sharptail sunfish, Masturus lanceolatus) by its tail while a second orca charged at high speed, releasing the fish just before impact. The collision produced an audible crunch and dispersed flesh and bone throughout the water. Juvenile orcas subsequently consumed the smaller fragments while adults fed on the main carcass.

SharpTail sunfish are among the world's heaviest fish, weighing up to 4,000 pounds and measuring up to 10 feet long. They are covered in thick, tough skin. Lead researcher Kathryn Ayres of the nonprofit Beneath The Waves captured the first recorded instance on July 29, 2024, on video while working as an ocean safari tour guide. A second instance was filmed by another tour operator in September 2025. Ayres noted that while orcas have previously been observed using coordinated ramming during hunts involving whale sharks, the outcome in these cases—the complete fragmentation of the sunfish—was unprecedented.

Scientists propose multiple explanations for the behavior. Breaking the sunfish apart may provide safer and more efficient access to nutrients by penetrating the thick skin. Alternatively, the behavior may aid feeding efficiency for younger orcas with smaller jaws, or facilitate food sharing among group members by dispersing the kill into smaller, manageable pieces. Researchers also note that orcas are known for playing with food and engaging in social behaviors without obvious practical purpose, such as carrying dead salmon on their heads or surfing in boat wakes. Monika Wieland Shields, director of the Orca Behavior Institute, stated she had never encountered reports of similar behavior and confirmed it as newly documented.

Orcas employ diverse hunting strategies depending on their population and prey. Typical sunfish predation involves targeting pectoral fins, slashing the body to remove viscera, and using the beak to access remaining tissue. The ram-to-fragment technique may represent a more sophisticated or cooperative variation. The findings, published in the journal Frontiers in Ethology, were made possible by increased use of underwater cameras and drones by eco-tour operators in the region. Researchers emphasized that continued collaboration with tour operators at respectful distances could reveal additional undocumented behaviors while minimizing disruptive impact on wildlife.